1. Field of the Invention
The present invention generally relates to an adjustable headgear, and, more particularly, to an adjustable headgear having a universal fitting cap for affixing a gas delivery mask to a patient, and to a system for supplying a flow of gas to a patient that incorporates such an adjustable headgear.
2. Description of the Related Art
There are numerous situations where it is necessary or desirable to deliver a flow of breathing gas, non-invasively, to the airway of a patient, i.e., without intubating the patient or surgically inserting a trachea tube in their esophagus For example, it is known to ventilate a patient using a technique known as non-invasive ventilation. It is also known to deliver continuous positive airway pressure (CPAP) or variable airway pressure, which varies with the patient""s respiratory cycle or with the patient""s condition, to treat a medical disorder, such as sleep apnea syndrome, in particular, obstructive sleep apnea (OSA), or congestive heart failure.
Non-invasive ventilation and pressure support therapies involve the selective placement of a patient interface device, which is typically a nasal mask, a nasal/oral mask, or a full face mask, on the face of a patient. The patient interface device communicates the flow of breathing gas from the ventilator or pressure support device with the airway of the patient, so that the therapeutic flow of breathing gas can be delivered from the pressure/flow generating device to the airway of the patient. It is known to maintain such interface devices on the face of a wearer by a headgear having upper and lower straps, each having opposite ends threaded through connecting elements provided on the opposite sides and top of the interface device, such as a mask. Because such masks are typically worn for an extended period of time, it is important that the headgear maintain the mask in a tight enough seal against a patient""s face without discomfort.
One such headgear is disclosed in U.S. Pat. No. 5,517,986 (xe2x80x9cthe ""986 patentxe2x80x9d). The headgear includes a headpiece 12 adapted to fit the crown and back of a patient""s head. Lower straps 30 and 32 provide a two-point connection with a gas delivery mask 40. See FIG. 1 of the ""986 patent. Depending straps 18 and 20, depending from headpiece 12, are connected to and moveable relative to the lower straps. Additionally, a pair of upper straps 56 and 58 can be used to provide a four-point connection with the gas delivery mask if needed. See FIG. 7 of the ""986 patent. While the headgear disclosed in the ""986 patent is adjustable it lacks adjustability in the cross direction of the head.
Accordingly, the present invention provides a universally adjustable headgear that is readily adjustable to affix a patient interface device, such as a mask, to a patient to create an effective seal between a gas delivery mask and the patient. The present invention further provides an adjustable headgear which is comfortable on the patient and fits a wide range of head sizes.
The headgear of the present invention includes a headpiece or cap portion that is adjustable in the cross direction of the patient""s head to control the circumference of the headpiece. The headpiece includes adjustment straps which adjustably connect to each other on the sides of the head. The headpiece further includes connecting straps to adjustably connect the headgear to a patient interface or gas delivery mask. The present invention further comprises an assembly including an adjustable headgear having a universal fitting cap and a gas delivery mask, and to a system for supplying a flow of gas to a patient that incorporates such an adjustable headgear. The headgear of the present invention fits a wide range of head sizes and shapes, is easy to use and provides increased stability.
These features and characteristics of the present invention, as well as the methods of operation and functions of the related elements of structure and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. It is to be expressly understood only and not intended as a definition of the limits of the invention.